One of the challenges for educators working in multilingual settings has been to identify the causes of reading difficulties of language learners (LLs). It is difficult to distinguish between reading problems stemming from low levels of linguistic proficiency versus more general reading/learning difficulties. There is now growing research evidence of cross-language transfer in different literacy processes. Literacy components that reflect language-independent, metacognitive/metalinguistic processes show similarities across the two languages of students. Some examples are phonological awareness, syntactic awareness, knowledge of genres and meaning-making strategies. A possible way to use cross-language transfer as a diagnostic tool is proposed. If children have had enough exposure to and possibly instruction in their first language (L1), we can assess their skills and insights in L1. For LLs who have these skills and insights in their strong L1, we can expect transfer to their second language (L2). If they do not have these skills and insights in their L2 yet, it indicates a delay due to limited language proficiency, and not because of a disability. This way LLs who just need more L2 practice and exposure can be distinguished from those LLs who truly have special needs.